Contamination of Urban Indian Environment by Hazardous Industries

Kausalya Ramachandran
Senior Scientist

D. Sai Kiran
Research Associate

M. Kalpana and M. Purnendu
Project Associates
CRIDA (ICAR), Santoshnagar, Hyderabad – 500059

Abstract
Rapid industrialization, urbanization and development of transport network have added impetus to economic development at the cost of environment. Although such development is integral to economic growth problem lies in their unfettered proliferation in India, leading to severe environmental degradation particularly since 1970. Metropolitan region often act as nodes for concentration of economic and political power resulting in rapid changes in land use / land cover in their neighborhood indicating environmental degradation. Sectoral shift in land use, i.e., from agriculture to urbanization or industrial use are significant indicating decimating role of agriculture in the region and hardship to rural people. Ill-planned industrialization has caused large-scale contamination of natural resources, viz., surface and ground water and soils. Scattered location of hazardous chemical industries in urban areas and meager availability of proper waste management system in Hyderabad, Banglaore, Chennai and Delhi, are primary cause of non-point source pollution in these urban centres. ARCGIS was used in tandem with satellite data (IRS – 1D – LISS III& PAN merged data) to map location of hazardous industries in these urban areas and estimate the spread and direction of flow of contaminants. The pattern and extent of contamination of soil and water was mapped and quantified to facilitate undertaking of remediation plans.

Introduction
Industrialization has provided livelihood and opportunities to millions in urban India. However, it has also brought in its wake problem of waste disposal, contamination of environment – air, soil, surface water bodies and ground water aquifer etc. which have resulted in contamination hazard imperiling human beings, livestock and plant life. Lack of proper planning in siting of industrial units, inadequate development of infrastructure, and lack of waste management facility etc., have precipitated this debacle, turning most of them into environmental flashpoints. Urgent measures for amelioration, waste management, recycling, waste minimisation, punitive action against defaulters etc., would facilitate halting of damage to ensure recovery (Biswas, 1997).

To achieve this objective, an inventory of contaminated sites around hazardous chemical industries was prepared. Firstly, hazardous industries and their locations were listed. Subsequently, the study areas were prioritized based on extent of contamination. Later these sites were studied using satellite data from IRS -1D LISS-III & PAN for assessing change in NDVI. ARCGIS was employed to overlay and analyze soil, geology, drainage pattern, water bodies, ground water aquifers, slope, etc. to estimate pollution hazard and extent of contamination. This strategy facilitated the environmental audit besides assisting in physical and fiscal planning for initiating ameliorative measures.

Industries producing inorganic chemicals, fertilizers, dyes, paints, pharmaceuticals and battery were identified as hazardous as their waste is non-degradable and tedious to recycle (GPCB & CPCB 1997). Concentration of these industries in various parts of India, were identified based on the lists provided by various State Pollution Control Board. The present study illustrates the methodology of environmental audit of four metropolitan areas in India – Hyderabad, Banglore, Chennai and Delhi using satellite data and GIS.

Study Areas
An area of 3062 km2 around Bangalore extending between 12° 55′ – 13° 15′ N and 77° 15′ – 77° 45′ E as depicted by SOI toposheet no. 57G/ 6, 8, 57H/5, 6, 10,12, 13 and 14 was studied. The region comprises of shallow gravelly soils with steep slope inducing severe erosion and also deep well-drained soils (100 cm) suitable for agriculture which makes it highly vulnerable to serious ground water contamination. Around Chennai over 3041 km2 extending from 12° 30′- 13° 15′ N and 79° 45′- 800 30’E (SOI toposheet no. 66C/4, 8, 66D/1,2 and 57P/13) was studied. The region has predominantly alluvial soils with large patches of red, black and laterite soil which are fertile and highly valuable for paddy cultivation; chemical contamination of the region would have severe repercussions.

An area of 2760 km2 lying between 77° 00′-77° 30′ E and 280 15′ – 29° 00′ N (SOI topo sheet no. 53H/1, 2, 3 and 6) around Delhi was studied. Alluvial soil and shallow water table owing to R. Yamuna make the region highly vulnerable to widespread chemical contamination. Around Hyderabad an area of 2934 km2 extending between 78° – 78° 45′ E and 17° 15′ – 17° 45′ N (SOI toposheet no. 56 K/2, 6, 7 and 11) was studied. The study area belongs to Deccan plateau and its undulating terrain with red and mixed red soils spotted with numerous water bodies is invaluable to the rural and urban areas and vulnerable to contamination hazard (Kausalya Ramachandran, 2001).

Material & method
Baseline information on land use / land cover of the regions for 1971, were generated from SOI toposheet and compared with IRS-1D LISS-III & PAN data of March 2001 using Land Use classification given by NRSA (1987). Land use and land cover maps of the four study areas were analyzed in ARCGIS and change detection indicating degradation of resource quality was performed. Using slope information the four study areas were delineated into watersheds for assessing flow-path of pollutants and spread of contamination in soil and surface water around the factory site. Normalized differential vegetation index (NDVI) was used to observe vigour of vegetative growth to correlate the impact of contamination. To assess water quality in various surface water bodies, characteristic reflectance curves were generated to establish a relationship between pollution status of a water body and its spectral digital values.

Discussion

Land Use alterations and Land Cover modifications
Alteration and modification of land use and land cover are indicative of processes of change that may lead to positive impact on development or denote resource degradation. Study of these resources using satellite data on a temporal basis would yield information on impact trends. For an insight in this aspect, satellite data from IRS 1D (LISS – III & PAN) were interpreted with older sets of data from IRS -1A / 1B, LANDSAT -TM in conjunction with SOI toposheet to reveal trends in change.

Based on this analysis it was found that Hyderabad metropolitan region had changed drastically. While in 1971, agriculture was dominant accounting for 62.6 % area with open scrub, settlement and water bodies accounting for 15, 5.7 and 5.6 % respectively. However, by March 2000 agriculture had lost its preeminence to urbanisation and built-up area accounted for 43% of the study area (Purnend et al 2001). There was a corresponding decrease in area under open scrub (4.2%) and water bodies (2%) and the number of water bodies decreased from 1271 to 960 during the corresponding period. Besides this, catchment of major water bodies in the region, viz., Himayat Sagar, Osman Sagar and Hussain Sagar were severely encroached upon adversely affecting inflow and decreasing dilution potential (Fig.1).

Fig. 1 Change in Land Use/ Land cover and decrease in agriculture (1971 – 2000) in 30 years
Similarly, Bangalore metropolitan region witnessed tremendous change in land use and land cover owing to urbanisation and industrialisation. While agriculture was predominant in 1971 (64.82 %), wasteland, built-up area and water bodies occupied 11.8, 5.4 and 3.6 % of the study area, respectively. By March 2000 built-up area increased to 13.3 % of the study area while wasteland and water bodies shrank to 8.6 % and 4.1% respectively.

In Chennai, population density increased tremendously during the corresponding period. In 1971 agriculture was dominant with 57.4 % of the study area while open scrub, built-up land and water bodies occupied 7.2, 10.1and 12.8 %. However by March 2001 agriculture was restricted to 43.5 % while built-up area increased to 20.6%. There was a decline in area under open scrub, water body, reserved forest and mud flats along the coastline.

  There has been a massive population explosion in Delhi during this period. It increased from 4 million in 1970 and 13.7 million in 2001 which was accompanied with massive growth in industrial activities. However due to absence of any zoning regulation or a comprehensive plan for urban development, most industries were located haphazardly leading to overcrowding, traffic bottlenecks and unhealthy living conditions as many industries were located in residential areas.

In 1970 agriculture was predominant in 61.2 % area while built-up land accounted for only 16.8 %. However, by March 2001, built up area doubled to 34.2 % and several large chunks of agricultural land were moved to other sectoral uses causing massive displacement of rural population and forced migration. Table 1 illustrates the trends in land use and land cover in these four metropolises.
Table 1: Change in land use in the metros between 1971 & 2000 (area in km2 )

Table 2 depicts the environmental scorecard with reference to trends in land cover changes and quality of portents of environment, namely, productivity potential, biodiversity, water quality and quantity and organic carbon (OC) content in soil.

Non-point source pollution owing to industrialization
To assess contamination in soil, water and general environment, the study area were delineated into watersheds to specify the direction of contaminant flow and its hazard potential. Bangalore region was demarcated into 10 watersheds with Suvarnamukhi Halla watershed being the largest (155.2 km2 ) with a maximum number of hazardous industries, i.e., 44 industrial units including 19 of paints and 22 of pharmaceuticals. Spectral reflectance from 37 water bodies spread in the region were assessed and 10 of them were found to be polluted (Fig. 2).

Fig. 2 Soil types around hazardous industrial nodes in Banglore region

    In Chennai region, watersheds of Thiruvallur, Avadi, Ennore, Manali, Kanchipuram Alltur, Marai Malainagar, Nandambakkam, Pallavaram and Sriperumbudur are endangered owing to contamination. However the situation is grave at Avadi and Ennore in Thiruvallur district.

In Delhi region, watersheds of Kirtinagar and Okhla were studied. While Okhla faces contamination hazard from pharmaceutical units, Kirtinagar is being contaminated by Dye industry. The other two industrial areas which threaten the Delhi environment are Gurgaon and Sonepat.

Spectral reflectance from water bodies in the red and infrared bands are indicative of the water quality as they would be nearer to one another or even overlap in case of polluted water with DN in red band ranging from 40 -50 and in IR between 40 -55. Reflectance curves from Yamuna and Hindon river indicated that they were polluted.

In Hyderabad region there are 159 industrial units producing hazardous substances. Although MOEF – GOI guideline restrict locating any polluting industry within 15 km of a fresh water body, in case of Patancheru – Gaddapothram – Bolaram industrial area, R. Nakkavagu, a principal tributary of R. Manjra drains the area. Nakkavagu is located within 5 km from Patancheru IDA and although the slope is < 1%, the sediment load and contaminant flow poses serious hazard to Manjira water supply system. Katedhan IDA located towards the south of Hyderabad is another contaminated area. The Balanagar - Jeedimetla - Kukutpalli IDA which drains into Hussain Sagar is also highly polluted and poses serious contamination hazard to the groundwater in residential colonies at the lower end. Estimation of spatial extent of contaminated area using GIS
It was possible to delineate and map contaminated sites along the water courses and around the factory sites using GIS. The contaminated streams were identified and buffer zonation was performed. Buffers of 100, 200, 500 m on either side of the stream / drainage channel were drawn (Fig.3). Factory sites were identified as nodes and buffering with lateral distances of 500, 1000, 2000 and 5000 m were drawn. Distances for such analysis have been recommended by CPCB which were adhered to. In Chennai region the Avadi watershed with an area of 110 km2 is the largest and most contaminated site. Around Delhi, Kirtinagar and Sonepat watersheds with small areas of over 20 km2 each were found to be contaminated. Around Hyderabad, the Patancheru IDA with an area of over 726 km2 is the largest industrial and also the most contaminated area (Table 3).

Fig 3. Buffer zoning to estimate extent of contamination
Table.3: Spatial extent of contaminated area in four metros

Pollution potential of hazardous industries were also assessed based on the medium that would be contaminated by the industry namely, air, water, soil or through dumping of solid waste on or beneath the surface. Table 4 illustrates the hazard potential of diverse industries in the numerous industrial areas around Hyderabad.
Table 4: Pollution potential of hazardous industries

Source: APPCB, Hyderabad & CPCB (1997)
Conclusion
Evidently non-point source pollution is a growing menace in urban areas in India especially in the fast growing metros of Delhi, Chennai, Hyderabad and Banglore. Industrial development must be undertaken in strict adherence to the Land Use Plan of a region and siting of hazardous industries must be undertaken with due care. There is an urgent necessity to evolve mechanisms to reduce waste generation and to recycle waste more efficiently in order to protect the environment. GIS and Remote Sensing are effective tools to study and analyse environment degradation. While GIS provides a comprehensive tool for assessing the impact of pollution both from point- as well as non-point sources, satellites provide real-time and temporal data on state of environment which can be used for such study. A combination of both techniques is useful for environmental auditing.

Reference

• Biswas, D. (1997): Controlling Water Pollution, Yojana, 8: 96-98.
• CPCB & GPCB (1997): Zoning atlas for siting of industries, CPCB, EMAPS/8/1997-98, Environmental planning & mapping series, New Delhi.
• Kausalya Ramachandran (2001): Assessment of contamination of Natural Resource using GIS and Remote Sensing – a study of Hyderabad region. GIS India – Jan – Feb 2001, p. 8 -13.
• NRSA (1987): Land Use Classification Key. NRSA, Balanagar, Hyderabad, India.
• Purnend, M., Sai Kiran, D. & Kausalya Ramachandran (2000): Indian Remote Sensing Satellite Data for Environmental Auditing of Hyderabad Metropolitan Region, ICORG-2000, Hyderabad.